How to get high quality pipe reducer?

A pipe reducer is the component in a pipeline that reduces the pipe size from a larger to a smaller bore (inner diameter).The length of the reduction is usually equal to the average of the larger and smaller pipe diameters. There are two main types of pipe reducer: concentric and eccentric pipe reducers.

Types of pipe reducersConcentric Reducer
Concentric Reducers are used to join pipe or tube sections on the same axis. They provide an in-line conical transition between pressurized pipes of differing diameters. A pipe reducer can be a single diameter change or a multiple diameter change. The pipes cannot recognize what the outside configuration of the pipe reducer looks like. The pipe flow is affected by the inside diameter conical transition configuration which can be axially moved and externally reconfigured to provide for more economical reducer fittings. Thus, concentric reducers connect pipes of unequal size but have a common centerline. In other words, it is a type of pipe fitting with different size ends to join pipes of different diameter that joins pipe sections on the same axis.

Seamless concentric reducer

Butt-welded concentric reducer

High pressure concentric reducer

Low pressure concentric reducer

As shown in Fig. 1. In this type of reducers area reduction is concentric and center line of the pipe on bigger end and smaller end remains same. These styles are normally used for vertical lines.

Fig.1: Concentric Reducers

Concentric reducers are designed with the small and large diameters on opposite ends and joined by a cone shaped transition section. They are available in both seamless and welded construction.How to take measurements of concentric reducers?Get the measurements of outer diameter (OD) and inner diameter (ID) , height (H), and the total dimension (T1, T2).Uses of concentric reducers:Some uses of concentric reducers are as follows:Concentric reducers will transition gracefully between the piping and the pump.The concentric reducers help in transporting slurries or abrasive liquids.They are useful in services where cavitation is present.When transporting between flanges or pipes of different ratings and wear protection is necessary, concentric reducers are ideal.Concentric reducers are used in discharge of the pump.Eccentric ReducerAn eccentric pipe reducer fitting is manufactured with the smaller outlet off center to the larger end, which allows it to align with only one side of the inlet. The reducer must be installed with straight side up so that it can prevent trapping air at the pump suction. The eccentric pipe reducers allow simple connection of different sized pipes.

Large size eccentric reducer

Butt-welded Eccentrice reducer

Seamless Eccentric reducer

Welded Eccentric reducer

As shown in Fig. 2 , in this style of reducer there is an offset in between the center lines of bigger end and center line of smaller end. This offset or eccentricity will maintain a flat side either on top or on bottom side.

Fig.2: Eccentric Reducer

This offset or eccentricity can easily be found out by the following equation:

Eccentricity=(Bigger end ID-Smaller end ID)/2

While using this type of reducer the user has the option of orienting the flat side. Usually for horizontal lines, eccentric reducers are oriented with either the flat side up or down and the same with deviation is mentioned in isometric.

Normally eccentric reducers with flat side down are preferred for following cases on horizontal lines:• On Sleepers and Piperacks• On lines requiring gravity flow• On pump suction line which handle slurry.

Eccentric reducers with flat side up are used for all pump suction lines (excluding pumps handling slurry) on horizontal lines. This way one can avoid air getting trapped inside the pipeline during initial venting through pump casing and will help in avoiding Cavitation.

Uses of eccentric reducers:Keeping big pipes and small pipes together.Reducing noise and vibration at the same time.Requires less installation space.Absorbs pipe wall and fluid borne noise.Less turbulence or material entrapment.Eccentric reducer are used with flat side up in pump suction to avoid cavitation.

Butt Welding reducers: The applicable pressure rating, dimensional and material standards for butt welding reducers are same as those applicable to butt welding elbows.

Socket welding reducers: As shown in Fig.3. such reducers are available in concentric type only & in the form of a coupling with one end socket to fit larger diameter pipe and other end socket to fit smaller diameter pipe. Standards are same as those applicable to socket welding elbows.

Fig.3: Socket Welded Reducers

Screwed reducers: Available only in concentric type and are in the form of coupling having one end to fit bigger pipe and other end to fit smaller pipe. ASME B16.11 is applicable dimensional standard. Material standards including pressure ratings are same as of screwed elbows.

Flanged reducers: Their pressure rating, use, material and dimensional standards are same as those applicableto flanged elbows. Regardless of reduction their face to face dimensions are governed by the larger pipe size.

Dimensional tolerances are in millimeters unless otherwise indicated and are equal ± except as noted.

Note:MSS SP-43 only covers stainless steel buttweld fittings made for use with Schedule 5S and 10S pipe and Stub Ends suitable for use with Schedule 40S pipe, as defined in ASME B36.19. The dimensions and dimensional tolerances defined in MSS SP-43 are substantially the same as those in ASME B16.9 specifications from NPS 1/2 – NPS 24. Except with regard to the outside diameter at the bevel.

Stainless steel reducer is a kind of fitting that be used for reducing piping size. Concentric reducer is most commonly used and often eccentric reducer used in piping in about pump and pipe rack area.

Stainless steel reduceris used for pipe diameter changes in a pipe. Usually adopted for reducing the forming process of pressing, expanding to suppress or reducing and expanding, to certain specifications of the reducer and stamping can be applied.A. reducing forming/hole enlargementReducer reducing forming technology is will be equal and reducer big end diameter of tube rounds into the forming mould, through along the axial direction of tube billet, shrink along the cavity movement and metal forming. According to the size of the reducer reducer, divided into the one of pressing or more press forming.Forming hole diameter is less than reducer big end diameter of the tube billet, used in die forming along the tube billet diameter hole enlargement. Hole enlargement technology mainly to solve the reducer in the variable diameter is larger not easily by reducing forming, sometimes according to the requirements of the materials and products forming, expanding and reducing method of combination.In the process of reducing or expanding deformation, according to different materials and variable diameter, determination by cold pressing and hot pressing. Under normal circumstances, as far as possible by cold pressing, but the multiple variable diameter and cause serious work hardening of the thick or alloy steel, wall thickness of materials appropriate USES hot pressing.B. stampingIn addition to the use of steel tube as raw material to produce reducer, the part of the specifications of the reducer can also be used steel plate stamping forming technology is adopted to improve the production. Drawing die shapes used by reference to reducing tube surface size design, use after blanking punching die, stamping steel stretch forming.The stress distribution and deformation characteristics:(1) the inner pressure function similarly hereinafter heartreducer an area about the size of the pressure difference between the bending moment caused by big end is relatively open, small end relative shrinkage phenomenon;

(2) the internal pressure under the action of eccentric reducer in central eccentric side inside the big end surface and eccentric side to the outer ring stress is the largest.

Reducers be applied, to change from pipe diameter in one direction. Standard there are 2 possibilities, the concentric reducer, is usually used in vertical pipe lines, and the eccentric reducer that is used in horizontal pipe lines.

The large sizes steel pipe reducers are commonly made from the steel plates, the production method is nearly same with the large sizes steel elbows production . Pressing and forming the steel plates to the shape of a reducer then welding the seam . The heat treatment and RT inspection is also necessary for the quality assurance.